matrix_to_rot_scale — REPRCONV algebra op

Data kinds: matrixrot_scale

Call: import reprconv; reprconv.matrix_to_rot_scale(matrix) (or opsreprconv.get("matrix_to_rot_scale"))

Usage

A 2-D similarity transform `(2,2)(angle [deg], scale). The inverse of :func:rot_scale_to_matrix`.

> The detailed description below is the original text — the summary and the headings are translated.

倍率は列ノルム、角度は `atan2(m[1,0], m[0,0])`。

せん断を含む一般の (2,2) を渡しても例外は出ない(相似成分だけを読む)ので、

`residual が要るときは呼び出し側で m - rot_scale_to_matrix(...)` を取ること。

Args:

matrix: (2, 2)。

Returns:

2-tuple の float `(angle_deg, scale)`。

Raises:

ValueError: (2,2) でない / 退化(倍率 0)/ 非有限。

References (sample data, literature)

• Sample-data catalog (download URLs / licences) — 2-D uses skimage.data (BSD/public domain) plus synthetic images; 3-D lists download URLs for real data sources (Stanford, PDS, …).

• Operator provenance and references — the sources of the research/methods this op family came from.

• The canonical algorithm (author, year) and its uses are named in the family usage guide above.

Runnable examples (verified samples that actually call this op)

representation_conversionpy -3.11 examples/representation_conversion.py

Ops the type connects to (they accept rot_scale as input)

rot_scale_to_matrix

Same category (algebra)

angle_to_matrix · matrix_to_angle · rot_scale_to_matrix · shift_to_vector · vector_to_shift · cscalar_to_polar · polar_to_cscalar · countrate_to_counts


*Provenance: reprconv.py — REPRCONV operator registry. This per-op note is generated by tools/opdocs.py md (do not hand-edit).*

© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.